The next mouse to test was the Microsoft Intellimouse Explorer 3.0, recently re-launched due to huge demand particularly from gamers.

Click for larger photos

The IE3.0 is a little bigger than the WMO, and is ergonomically designed for right handers. The design has a few more frills, being made up of metallic grey plastic shell against darker grey rubberised features. There are five buttons on the mouse including the wheel and two on the left side.

I'll only paste the final response graphs now, without the raw data plots.

MS Intellimouse Optical 3.0 (125 Hz) Response Graph

MS Intellimouse Optical 3.0 (1000 Hz) Response Graph

The IE3.0 response graphs at 125 Hz and 1000 Hz are identical to the WMO, so I would conclude that they share the same optical hardware.